Slip coupling drive assembly



March 18, 1941. A. KUHNS SLIP COUPLING DRIVE ASSEMBLY Filed Aug. 14, 1959 Patented Mar. 18,1941 2 UNITED STATE s PATENT OFFICE sur courrlma mvr. Assam! Austin Kuhna, Buffalo, N. YL, assignor to Farrel- Birmingham Company, Incorporated, Buflalo,

N, Y., acorporation of Application August 14, 1939, Serial-No. zsaasa f2 Claims. (01. 74-410) 10 which support the driven elements of the slip couplings whose driving elements are connected with driving sources, such as Diesel engines. For

eiiicient operation in installations of this,type, the

bearing support and driving of the pinions-must 15 be such that correct gear-tooth alignment and p mesh of the pinions with the driven gear will be maintained under. all conditions of operation.

In a drive assembly where the coupling element is mounted on one end of a shaft and this shaft 20 extends through the tubular shaft of the driving pinion. the heavy overhung coupling weight must be efllciently taken care of so that it will not interfere with the free movement of the driving pinion to maintain its proper toothed alignment at and mesh with the driven gear. An important object of my invention is therefore to isolate and eliminate entirely the effect of the heavy overhung coupling weight on the support and arrangementrof the driving pinion, and I pref so erably accomplish this by using separate bearings for the pinion shaft and the slip coupling shaft and the provision of a flexible coupling between the shafts so as'to entirely free the driving pinion so that it may accurately and em- 35 eiently maintain its proper meshing condition with the driven gear under all conditions of operation. v i

My invention is incorporated in the structure disclosed on the drawing, in which drawing: Figure 1 is a more or less ditic plan view of a propulsion system to which my invention may be advantageously applied; and

s Figure 2 is an enlarged section on the'plane 11-11 of Figure 1. 5 On Figure 1, I have shown a propulsion system in which my inventionmay he advantageousiyused. The system shown comprises a gear G mounted on the shaft II which is iournaled in thrust bearings II and connected by a 50 suitable coupling l2 with'the propeller shaft 13 on which a propeller it may be rnoimted. At its opposite sides the gear is meshed by drive pinions P of the drive assemblies. The pinions are driven through sllpcoupling structures 55 by driving sources, such as Diesel engineae tion between the is suddenly reversed,wh

Figure 2 shows the details of. arrangement and operation of the drive assemblies. A strong, ri id supporting framework or foundation structure It provides for each assembly a pair of inner bearing structures It and I1 and outer bearing structures and is, the bearing struc- 1 ture I] being adjacent to the inner bearing 16, 4 and the bearing It being disposed-a distance outwardly from the inner bearing II. The inner bearings Ii and I1. journal a tubular shaft rotor the pinion P, and the piniomand shaft may be an integral'structure; Extending through the pinion shaft and journaled in the outer bearings 18 and I9 is a coupling shaft 2! which, adjacent to the bearing I8, is secured to the external member 22 of a slip coupling which, as shown, may be of the electric type. a The internal member 23 of the coupling is secured to the'shaft 24, which shaft is connected by -a coupling 25 with the shaft 26 of a source 3 (Figure l).v

At its outer end, the shaft 2| is in drivin connection with the outer end of the-pinion shaft through a flexible coupling F. As shown, this coupling may be of the dental type. The pinion shaft terminates in a flange 21 to which is-secured an internal gear ring 28 which meshes with a gear 2! keyed to the shaft 2|.

Inthe-bearing is, there is provided a bearing shell 30 for the shaft 2|, and the shell preferably 30' has a lining. of anti-friction material, such as babbitt. ,The shell has end flanges" engagin shoulders on the bearing so as to hold the shell against-axial movement in the bearing, and the shaft has tlons as a thrust bearing tending to hold the shaft 2i against axial displacement. The outer bearing is of the shaft is also provided with a babbitted bearing shell 34. The entire weight of 40 the shaft 2| and the coupling element 22 carried I thereby is borne by the bearings is and is, there being ample clearance space between this shaft and the pinion shaft 2fl'so that-the only connecshafts is through the flexible coupling F. j

1 In thebearings II and I1, bearing shells 35 are provided, and there is suflicient clearance between .the pinion and the ends of the bearings. to

permit axial shift of the pinion shaft in the bearto v ings. Although the'shaft it for the gear G is mounted in thrustbearings which tend to hold the shaft against axial displacement, there are abnormal conditions. such 'when the propeller xabnormal pleasure.

abutment collars 33 abutting the ends 35 of the shellac that the bearing-structure funcmay cause slight axial displacement of the gear shaft. However, with the pinion shafts free to shift axially, the pinions are enabled to follow any such axial movement of the gear shaft and gear so as to maintain proper meshing engage- I ment.

In the flexible coupling connection F between the drive shaft 2| and the pinion shaft, there is suiiicient clearance between the coupling elements to permit axial shift of the pinion shaft to follow any axial displacement of the. driven gear, and the tooth arrangement of the flexible coupling is also suchthat any axial mis-alignment of the shaft 2| relative to the pinion shaft will not cause any strain. on the pinion shaft. Any pressure caused by axial misalignment of the shaft 2|, which might be occasioned by the overhung weight of the slip coupling during operation of the driving assembly, will be taken up and absorbed by the bearings l8 and IQ for the shaft 2| and will not be transmitted through the flexible coupling to the pinion shaft.

' Thus, the effect of the heavy overhung slip coupling weight is isolated from the pinion structure, and the pinion structure may at all times freely and independently operate to insure correct tooth alignment and meshing with the driven gear under all conditions of operation. This is of particular advantage where the pinions and gears are of the helical or herring-bone type.

I have shown a practical and efllcient embodiment of the features of my invention, but I do not desire to be limited to the exact construction and arrangement shown and described, as changes and modifications may be made without departing from the scope of the invention.

I claim as follows:

1. A transmission assembly comprising a, gear to be driven and a supporting shaft therefor mounted in thrust bearings tending to prevent axial displacement of said shaft, a pinion meshing said gear, said pinion and gear-being of the herring-bone type, a tubular supporting shaft for said pinion, plain bearings for said pinion shaft adjacent opposite sides of said pinion and providing suflicient clearance for axial movement of the shaft therein, a drive shaft extending through said pinion shaft but radially displaced therefrom, bearingsfor the ends of said drive shaft said gear at all times.

located outside of said .piiiion shaft bearings, a slip coupling having one of its elements adapted for connection witha driving source and its other element mounted on one end of said driving shaft to be supported solely by said shaft, 9. flexible coupling between the other end of said drive shaft and the adjacent end of said pinion shaft, means holding said drive shaft against axial movement in its bearings, said flexible coupling being arranged to transmit the rotary movement of said drive shaft to said pinion shaft and pinion without causing any strain on the pinion shaft during any misalignment of said drive shaft relative to said pinion shaft and to permit free axial shift of said pinion shaft for movement of the pinion to follow any axial displacement movement of said gearshaft and gear whereby proper meshing relation will be maintained at all times between the pinion and gear.

2. A driving assembly comprising a pinion of the helical tooth type for meshing with a gear to be driven, a tubular supporting shaft for said pinion, plain bearings for said pinion shaft adjacent opposite sides of said pinion and providing suflicient clearance for axial movement of the pinion shaft therein, a drive shaft extending through said pinion shaft; a slip coupling driving element secured to one end of said driving shaft,

two bearings for said driving shaft located outside of said pinionshaft bearings for supporting the entire weight of said driving shaft entirely independently of said pinion shaft and its bearing, one of said driving shaft bearings being between said driving element and the corresponding bearing for said pinion shaft and close to said pinion shaft bearing and the other bearing for said drive shaft being separated by a short space from the other bearing for said pinion shaft, and a flexible coupling in said space connecting said shaft and arranged to transmit the rotation of said driving shaft to said pinion shaft without any strain on the pinion shaft during any axial misalignment of said drive shaft and arranged to permit the axial movement of said pinion shaft independently of said drive shaft to maintain said pinion in proper meshed connection with AUSTIN 'KUHNS. 

